Spark-plug.



Patented May14,1918.

wir/155555 UNITED sTATEs PATENT oEEIoE.

FRANK GARACA, 0F IBESSEMER, ALABAMA.

SPARK-PLUG'.

vide spring means engaging one of the elec-- trodes and tending to forcethe same toward the other electrode.

A further object of the invention is to provide means for moving theelectrode longitudinally to compress or expand the spring.

Another object of the invention is to provide a device of thischaracter, which is simple and durable in construction, reliable andeflicient in operation and one which can be manufactured and placed uponthe market at a minimum cost.

The invention also consists in certain other features of constructionand in the combination and arrangement of the sev-A eral parts, to behereinafter fully described, illustrated in the accompanying drawingsand specifically pointed outyin the appended claims.

In describing my invention in detail, reference will be had to theaccompanying drawings, wherein like characters denote like orcorresponding parts throughout the several views, and in which:

The ligure represents a longitudinal sectional view through the sparkplug.

In this figure, l represents the outer metal shell of the plug providedwith thg usual screw threaded lower end for engaging with the screwthreaded hole in the cylinder` top. 2 represents the porcelain body heldin the shell by means ofthe packing nut 3.. 4 represents a movableelectrode'whichis in the form of a rod passing longitudii ally throughthe body 2 and provided with the screw threaded upper end which isadapted to receive the nut 5 and the binding Specification of LettersPatent.

Application led .T une 20, 1917. Serial No. 175,914.

Patented May 14, 1918.

tap 6. lne lower end of the rod `yl is pro- .vided with a collar 7 and acoil spring 8 surrounds the rod and bears against this -v collar, theporcelain body 2 having a recess 9 in its lower end for receiving saidspring and collar. A washer 10 ts in the bottom of this recess and hasan openin therein through which the rod 4 passes. T e spring 'iscompressed between this washer and the collar 7 and tends to force saidcollar and the rod downwardly, but this movement is prevented by the nut5 engaging the top of the body 2, so that by adjusting this nut theposition of said rod may be regulated; 1l indicates the stationarelectrode secured to l the lower end of the s ell 1 as usual.

It will be seen that the spring tendsto move the end of rod 4: intocontact with the end of the electrode 11 so that the space between theelectrodes is adjusted by means of the nut 5.

It is thought from the foregoing that the advantages, and novel featuresof my invention will be readily apparent.

I desire it to be understood that I may make slight' changes in theconstruction and in the combination and arrangement of the severalparts, provided that such changes fall within the scope of 'the appendedclaims.

I claim as my invention:

l. A spark plug comprising a shell,'a

porcelain body secured therein and having a vrecess in its lower end,stationary and .movable electrodes, means for adjusting the movableelectrode, with relation to the stationary electrode, andyieldable meansassociated with said movable electrode and adapted to lbe arranged insaid recess.

2. A spark plug :comprising a stationary and movable electrode, saidmovable elec. trode consistin of a rod passing through the body of tlreplug, said rod having a screw threaded upper end, a nut engaging saidend and bearing against the top `of the plug, a collar on the lower endof saidrod and a spring compressed between said collar and a part of theplug.

3. A spark plug comprising a s hell'and a porcelain body held therein,said body having a recess in its lower end, stationary and movableelectrodes, said movable electodes consisting of a rod passing throughthe body and through said recess, said rod having a screw threaded upperend, a, nut engagng with said upper end, a collar on said rod and a coilspring in the recess and engagng said collar.

FRANK GARACA.

Witnesses:

W. C. BATY, E. E. WILSON.

